
Modular Open Systems Approach
Modular Open Systems Approach
A Modular Open Systems Approach (MOSA) is an integrated business and technical strategy to achieve competitive and affordable acquisition and sustainment over the system life cycle. In the development of Department of Defense (DoD) systems, MOSA is an acquisition and design strategy, consisting of a technical architectures, that adopts open standards and supports a modular, loosely coupled, and highly cohesive system structure. MOSA implies the use of a modular design, including system interfaces designed according to accepted standards with which conformance can be verified. MOSA can be employed in both defense and non-defense sectors by using a modular architecture and an open business model to add, modify, replace, and remove system components across the acquisition life cycle.
DoD can use MOSA to design systems with highly cohesive, loosely coupled, and severable modules that can be competed separately and acquired from independent vendors. DoD is actively pursuing MOSA in the life cycle activities of its Major Defense Acquisition Programs and Major Automated Information Systems, keeping pace with the rapid evolution in technology and threats that require faster cycle time for fielding and modifying warfighting capabilities.
A key enabler for MOSA is the adoption of an open business model, which requires doing business in a transparent manner and leveraging the collaborative innovation of numerous participants across the DoD enterprise. This permits sharing risk, maximizing reuse of assets, and reducing ownership cost. MOSA allows the Department to incrementally acquire warfighting capabilities, including systems, subsystems, software components, and services, with more flexibility, competition, and innovation.
MOSA Benefits
There is no single, magic bullet for implementing MOSA. The user must determine the desired outcomes up front to fully realize its benefits. DoD seeks five primary benefits of MOSA:
- Enhance competition
- open architecture with severable modules, allowing components to be openly competed.
- Facilitate technology refresh
- delivery of new capabilities or replacement technology without changing all components in the entire system.
- Incorporate innovation
- operational flexibility to configure and reconfigure available assets to meet rapidly changing operational requirements.
- Enable cost savings/cost avoidance
- reuse of technology, modules, and/or components from any supplier across the acquisition life cycle.
- Improve interoperability
- allow severable software and hardware modules to be changed independently.
- Defense Acquisition Guidebook 3–2.4.1, Modular Open Systems Approach (2017)
- allow severable software and hardware modules to be changed independently.
The benefits to MOSA implementations complement one another, and it is likely that a program will seek to configure the benefits to achieve the necessary outcome.
Working Groups
To further the use of MOSA in defense programs, DoD Engineering leads a collaborative Modular Open Systems Working Group (MOSWG), whose participants represent multiple segments of the defense engineering and acquisition community, including Program Executive Offices, Program Managers, engineering, and science and technology proponents. The MOSWG promotes modular open engineering principles through the Services and other agencies and can assist in advancing modular open practices.
As a resource for MOSA practitioners in Government, industry, and academia, DoD Engineering manages the Modular Open Systems Community of Practice (CoP) website, hosted by Defense Acquisition University (DAU). The CoP site is open to the public. Users with a DoD Common Access Card may register with DAU and contribute comments and other content to the site.
Modular Open Systems Working Group
Membership: Program Executive Officers, Program Managers, engineers, science and technology components.
MOSA Community of Practice
Membership: Government, industry, academia
Website: Visit www.dau.edu website
Tri-Service Tiger Team
Membership: DoD, Service Leads, and Industry partners
Communities
Resources
- 10 U.S.C. 144, Modular Open Systems Approach
- Air Force AFI-63-101/20-101 Integrated Life Cycle Management, May 2017 (MOSA Instruction)
- Air Force Data Rights Guidebook, July 2019 (MOSA and IP Guidance)
- Army DA Pam 70-3 Army Acquisition Procedures, September 2001 (MOSA Instruction)
- Considerations and Examples of a Modular Open Systems Approach in Defense Systems, Philomena Zimmerman, et al., Journal of Defense Modeling and Simulation (JDMS) , April 30, 2018
- Defense Acquisition Guidebook 3–2.4.1, Modular Open Systems Approach
- Defense Acquisition University (DAU) Glossary: Interoperability
- DoD Instruction 5000.02T, "Operation of the Defense Acquisition System," Enclosure 3 (Systems Engineering), Section 14
- DoD MOSA Tri-Service Memo (MOSA for our Weapon Systems is a Warfighting Imperative), January 2019
- DoD Open Systems Architecture Contract Guidebook for Program Managers, v.1.1, DoD Open Systems Architecture Data Rights Team, June 2013
- Improving Transition: Modular Open Systems Approach (MOSA) and Engineering Enablers, Robert Gold, 19th Annual National Defense Industrial Association Systems Engineering Conference, Springfield, VA, October 26, 2016
- Modular Open Systems Approach (MOSA) Reference Frameworks in Defense Acquisition Programs.
- MOSA Community of Practice Terms and Definitions
- Navy DON Middle Tier Acquisition and Acquisition Agility Guidance OSA Strategy Letter
- Open Systems Management Plan (OSMP)
- Tri-Service Open Architecture Interoperability Demonstration (TSOA-ID), GTRI Conference Center Atlanta, GA, January 29, 2020
- Defense Standardization Program Journal, September-December 2019: Modular Open Systems Approach
Training and Education Resources
CLE 019 (DAU): This course describes MOSA principles from a business and technical perspective. It provides program examples of successful MOSA implementation, as well as sources that can assist an organization in implementing MOSA. This course is designed to familiarize students with MOSA best practices throughout the life cycle.
Definitions
The Tri-Service Tiger Team reviewed and updated the following definitions, which can be found in the DAU Glossary.
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